Докажи тождества: 1) \cfrac{36a}{9a^2-25}-\cfrac{3a-5}{3a^2+5a}-\cfrac{3a+5}{3a^2-5a}=\cfrac{2}{a}; 2) \cfrac{3a+5}{a^2+a+1}-\cfrac{7-a^2}{1-a^3}-\cfrac{2}{a-1}=0; 3) \cfrac{1}{(3a+2b)^2}-\cfrac{2}{9a^2-4b^2}+\cfrac{1}{(3a-2b)^2}=\cfrac{16b^2}{(9a^2-4b^2)^2}; 4) \cfrac{a-3}{b-5}-\cfrac{6a^2-7a-3}{3ab+b-5-15a}=\cfrac{a}{5-b}.

Задание

Выполни задание

Докажи тождества:

\(\cfrac{36a}{9a^2-25}-\cfrac{3a-5}{3a^2+5a}-\cfrac{3a+5}{3a^2-5a}=\cfrac{2}{a}\) ;
\(\cfrac{3a+5}{a^2+a+1}-\cfrac{7-a^2}{1-a^3}-\cfrac{2}{a-1}=0\) ;
\(\cfrac{1}{(3a+2b)^2}-\cfrac{2}{9a^2-4b^2}+\cfrac{1}{(3a-2b)^2}=\cfrac{16b^2}{(9a^2-4b^2)^2}\) ;
\(\cfrac{a-3}{b-5}-\cfrac{6a^2-7a-3}{3ab+b-5-15a}=\cfrac{a}{5-b}\) .